Facebook issues mystery invitation to media: What's it building?

Facebook's media invitation to a news conference at its Menlo Park,… (Facebook )

SAN FRANCISCO -- Facebook is holding a news conference at its Menlo Park, Calif., campus next week to unveil something new.

The giant social network sent out the invitation Tuesday. It said simply: "Come and see what we're building."

That was enough to unleash a feverish wave of speculation even in the blitz of coverage coming out of the Consumer Electronics Show in Las Vegas. It might just be a product launch, but we plan to treat it like a rocket launch.

Facebook used to have frequent news conferences before its less-than-impressive initial public offering in May. But it's been more than a year since the last one so the media are getting restless.

Some are wondering if Facebook will unveil a Facebook phone powered by Android mobile software it has modified. Chief Executive Mark Zuckerberg has repeatedly poured cold water on that hot rumor, saying it’s the "wrong strategy" for Facebook, which wants its service on all phones.

Others wonder if Facebook might make good on Zuckerberg’s pledge to roll out better search functionality. Facebook already receives 1 billion search queries a day, Zuckerberg said in September.